Vacuum pump



FIG. 1 is a front, left and bottom perspective view of a vacuum pump showing my new design;

FIG. 2 is a right, rear and top perspective view thereof;

FIG. 3 is a perspective view of the exploded view of FIG. 2;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left side view thereof;

FIG. 7 is a right side view thereof;

FIG. 8 is a top plan view thereof; and,

FIG. 9 is a bottom plan view thereof.

The broken lines in the figures illustrate portions of the vacuum pump that form no part of the claimed design. 

CLAIM The ornamental design for a vacuum pump, as shown and described. 